Silacyclopentane thiols and thiolates

ABSTRACT

SILACYCLOPENTANE MERCAPTANS AND THIOLATES OF THE FORMULA   1-(O(2-N-M/2)-XM-RN-),3-(Y-S-),3,4-DI(R&#39;&#39;-)SILACYCLOPENTANE   IN WHICH Y IS HYDROGEN OR AN ACYL GROUP, N IS 0 OR 1, M IS 0 TO 2, ARE PREPARED BY THE ADDITION OF H2S OR ACYL-SH TO THE CORRESPONDING SILACYCLOPENTENE IN THE PRESENCE OF FREE RADICAL GENERATORS SUCH AS PEROXIDES, AZOBIS-NITRILES OR ULTRAVIOLET LIGHT. SPECIFIC COMPOUNDS WHERE Z IS   3,4-DI(R&#39;&#39;)-1,3-SILACYCLOPENTYLENE   ARE HSZ(CH3)C1, (CH3COSZ(CH3))2O AND (HSZO)NTHE NOVEL COMPOUNDS ARE USEFUL AS LUBRICANTS, LUBRICANT ADDITIVES, AND CHEMICAL INTERMEDIATES.

United States Patent US. Cl. 260-448.2 N Claims ABSTRACT OF THEDISCLOSURE Silacyclopentane mercaptans and thiolates of the formula inwhich Y is hydrogen or an acyl group, n is 0 or 1, m is 0 to 2, areprepared by the addition of H 8 or acyl-SH to the correspondingsilacyclopentene in the presence of free radical generators such asperoxides, azobis-nitriles or ultraviolet light. Specific compoundswhere Z is are HSZ(CH )Cl, {CH COSZ(CH O and (HSZO),,. The novelcompounds are useful as lubricants, lubricant additives, and chemicalintermediates.

The compositions of this invention have various uses. The mercaptansshown herein are useful as lubrication additives for petroleum oils orother lubricants and as intermediates in the preparation oforgano-functional compounds containing other functions such as thecarboxyl. For example, one can add acrylic acid to a mercaptan of thisinvention to produce a compound having a carboxyl and a sulfur atomattached to the cyclopentane ring. Such derivatives are useful asadhesion promoters in silicone rubber.

The thiolates employed herein are useful as intermediates in thepreparation of the mercaptans.

This invention relates to an organosilicon compound of the formula inwhich Y is H or Y'C=O in which Y is a hydrocarbon or halohydrocarbonradical free of aliphatic unsaturation, R is independently hydrogen oran alkyl radical of from 1 to 6 carbon atoms, R is a monovalenthydrocarbon radical or a monovalent halohydrocarbon radical, X ishalogen, al'koxy, ketoxime, carboxyacyl, amineoxy or OH, R and X beingfree of aliphatic unsaturation, n is 0 or 1 and m is an integer from 0to 2,

' the sum of n+m being no greater than two.

This invention further relates to copolymeric siloxanes containing atleast one unit of the formula 3,655,713 Patented Apr. 11, 1972 lice inwhich n, and m are each 0 or 1 and Y, R, R and X are as above defined,the remaining siloxane units in said copolymer being essentially all ofthe formula in which R" is a monovalent hydrocarbon or monovalenthalohydrocarbon radical, or an X group and a has a value from 0 to 3inclusive.

As can be seen the compositions of this invention can be either silanesor siloxanes and the siloxanes can be either homopolymers or copolymers.

The thiolates of this invention are best prepared by adding thiolates ofthe structure YSH to where R, n, X and m are as above defined.

Where R is an aliphatic radical the best procedure is to react thethiolate with the silacyclopentene at about 50 C. with any free radicalinitiator such as benzoyl peroxide or azo-bis-iso-butyronitrile. Where Yis aromatic, however, the best method is to initiate the reaction withultraviolet light at a wave length of about 2537 angstroms or shorterwave lengths, under ambient conditions.

The mercaptans of this invention can be prepared by two methods. Themost general method is that of adding hydrogen sulfide to thecorresponding silacyclosilapentene. This method works with all silanesand all of the siloxanes. The best conditions for carrying out thereaction is to use a large excess of hydrogen sulfide and react it withthe silacyclopentene in the presence of ultraviolet light attemperatures of -20 C. or below. The excess of hydrogen sulfide shouldbe at least 10 mols of hydrogen sulfide per mol of olefin.

The second method of preparing the mercaptans is that of reacting thecorresponding thiolates with ammonia. This reaction operates with allsiloxanes and with those silanes in which X does not produce an acidicbyproduct upon hydrolysis. That is, X cannot be chlorine, acetoxy, etc.The ammonolysis is best carried out by reaction with ammonia in aprotonated solvent such as methanol. The reaction goes quite well atroom temperature.

Finally, the siloxanes particularly those containing units can beprepared by any of the methods normally used to prepare siloxanes. Theseinclude cohydrolysis of the corresponding silanes and the reaction ofsilanes and siloxanes containing SiX groups with siloxanes containingSiOH groups. All of these reactions are well known in the art.

The starting materials for the preparation of the compositions of thisinvention are known compounds and are described and claimed in US.Patent 3,509,191. Briefly, these silacyclopentenes are prepared byreacting butadiene or derivatives of butadiene with disilanes asdisclosed in said patent, the entire disclosure of which is herebyincorporated by reference.

Illustrative structure of the compositions of this invention are shownherein where Z is the structure Thus, the mercaptans of this inventioncan be siloxanes of the generic formula and combinations of HSZRO HS 2 oand ammo The homopolymers and copolymers can be any combination of theunits HSZRO HSZO and HSZXO in which R, X and Z can be the same ordiflerent groups. Z, of course, can vary by using various combinationsof R.

The thiolates of this invention can be of the generic formula Theseformulae include silanes of the structures YSZRX, YSZX and siloxanes ofthe unit formulae Y'SZRO Y'SZXO and Y'SZO. The homopolymeric andcopolymeric thiolate siloxanes can be any combination of units of thetype Y'SZRO. YSZXO. and Y'SZO. The copolymers can vary with respect tothe various types and combinations of Y, R, X and Z. One can also havecopolymers of any combination of and units of any combination of theformula R,,S1O 1 For the purpose of this invention Y' can be anymonovalent hydrocarbon radical free of aliphatic unsaturation such asalkyl radicals such as methyl, ethyl, isopropyl, octadecyl or myricyl;cycloaliphatic hydrocarbon radicals such as cyclopentyl, cyclohexyl ormethylcyclohexyl, aryl hydrocarbon radicals such as phenyl, xenyl,tolyl, xylyl, naphthyl or anthracyl and aralkyl hydrocarbon radicalssuch as benzyl, Z-phenylethyl, Z-phenylpropyl.

Also for the purpose of this invention Y can be any halogenatedmonovalent hydrocarbon radical free of aliphatic unsaturation such ashaloalkyl radicals such as chloromethyl, 3-chloropropyl, bromooctadecyl,3,3,3-trichloropropyl, chloroisopropyl of 2(perfluoroalkyl)ethylradicals in which the perfluoroalkyl radical is trifluoromethyl,perfluoroethyl, perfluoroisobutyl or perfluorooctadecyl; halocycloalkylradicals such as bromocyclohexyl, chlorocyclopentyl or fluorocyclohexyl,haloaryl radicals such as 2,4-dichlorophenyl, dibromoxenyl,a,cc,octrifluorotolyl, iodonaphthyl and tetrachlorophenyl andhaloaralkyl radicals such as 2(chlorophenyl)ethyl, p-chlorobenzyl or2(bromophenyl)propyl.

R can be hydrogen or any alkyl radical of from 1 to 6 carbon atoms suchas methyl, ethyl, butyl, hexyl or isopropyl.

R can be any monovalent hydrocarbon radical free of aliphaticunsaturation such as alkyl radicals such as methyl, ethyl, isopropyl,octadecyl or myricyl; cycloaliphatic hydrocarbon radicals such ascyclopentyl, cyclohexyl or methylcyclohexyl; aryl hydrocarbon radicalssuch as phenyl, xenyl, tolyl, xylyl, naphthyl or anthracyl and aralkylhydrocarbon radicals such as benzyl, 2-phenylethyl, or 2-phenylpropyl.

X can be any of the following groups which are free of aliphaticunsaturation. Halogen such as fluorine, chlorine, bromine or iodine;alkoxy groups such as methoxy,

ethoxy, isopropoxy, octadecyloxy, cyclohexyloxy, phenoxy, benzoyloxy,,B-phenylethyloxy, Z-chloroethyloxy, chlorophenoxy,3,3,3-trifluoropropoxy or bromocyclohexoxy; or 2-methoxyethyl,2-methoxyisopropyl, 2-butoxyisobutyl, p-methoxyphenyl or (CH 'CH O) CHany carboxy acyl radical such as acetyl, propionyl, benzoyl,cyclohexoyl, stearoyl, naphthoyl, trifluoroacetyl, chlorobenzoyl, orbromopropyl; or any amineoxy radical of the formula OB in which B is,for example, dirnethylamino, diethylamino, ethylmethylamino,diphenylamino or dicyclohexylamino, or any ketoxime radical of theformula -ON=CD or 0N=Fiy in which D is a monovalent hydrocarbon radicalsuch as methyl, phenyl, allyl, octadecyl, cyclohexyl, or benzyl and D isa divalent hydrocarbon radical such as pentamethylene, hexamethylene or2-methyl pentamethylene.

For the purpose of this invention R" can be any monovalent hydrocarbonradical such as alkyl radicals such as methyl, ethyl, isopropyl, hexyl,octadecyl or myricyl; alkenyl radicals such as vinyl, allyl, hexenyl;alkynyl radicals such as propargyl; cycloaliphatic radicals such ascyclopentyl, cyclohexyl or cyclohexenyl; aromatic hydrocarbon radicalssuch as phenyl, tolyl, xylyl, xenyl, naphthyl or anthracyl and aralkylhydrocarbon radicals such as benzyl, fl-phenylethyl, [i-phenylpropyl orgamma-tolylpropyl. In addition, R" can be any of the radicals shown forX above.

In these cases where R" contains aliphatic unsaturation and Y is H it isbest to stabilize the compounds with free radical scavengers such ashydroquinone.

The following examples are illustrative only and should not be construedas limiting the invention which is properly delineated in the appendedclaims.

EXAMPLE 1 64.6 g. of thiolacetic acid containing a catalytic amount ofazo-bis-isobutyronitrile was added to 128.0 g. of 1,1-dichloro-1-silylcyclopentene-3 with stirring over a period of minutes asthe flask was heated at 50 C. There was an exotherm to 80 C. during thereaction. The temperature was maintained at 50 C. by the rate ofaddition and by cooling. The reaction was stripped and the residue wasshown by nuclear magnetic resonance to be of the formula CHaC OS EXAMPLE2 The product of Example 1 was added to g. of refluxingmethylorthoformate over a period of 2. hours. 1 g. of methanol Was addedand the entire mixture was allowed to reflux for one hour. The productwas stripped at reduced pressure for one hour leaving 166.5 g. of 3-acetylthio-l,1-dimethoxy-l-silacyclopentane. This is a 89% yield. Thematerial had the formula of The structure was proven by nuclear magneticresonance spectra.

EXAMPLE 3 Ammonia was blown into a stirred solution of 166.5 g. of3-acetylthi-o-l,l-dimethoxy-l-silacyclopentane in 31 g. of methanol at atemperature of 60 C. for one hour. The methanol was stripped oif andthere was obtained acetamide and the product having the followingproperties: B.P. 54 C. at .1 mm. m, 1.4768, (1 1.0545, R observed .2677and R calculated .2687. The structure of the compound was furthercertied by nuclear magnetic resonance spectra.

the product 1 methyl-l-chloro-1-silacyclopentane-3-thiol B.P. 96 C. at24 mm.

EXAMPLE 9 EXAMPLE 4 A solution of 210 g. of Employing the procedure ofExample 1, l-chloro-l- CH3 methyl-1-silacyc1opentene-3, was reacted withthiolacetic I acid to produce a mixture of the cis and trans isomers ofthe formula 10 CH and 152 g. of thiolacetic acid containing 1 g. of azo-3 SKOHWI bisisobutyronitrile was irradiated with a heat lamp for 3 twohours and then stirred at room temperature for 6 days. The mixture wasdistilled to give 300 g. of having the following properties: n 1.5047,B.P. 63 C. at 1.5 mm. The structures were verified by nuclear CH3C=OSmagnetic resonance spectra. Si 0 E PLES BP 120C t01 I 15175 da' l105Employing the procedure of Example 2, the product a an 4 of Example 4was reacted with methanol to produce a EXAMPLE 10 mixture of the cis andtrans isomers of the formula CHQGOS 300 g. of the product of Example 9was suspended l SKCHMOC in 150 g. of water and 150 g. of methanol andammonia gas was added with rapid stirring. After complete conversion ofthe ester to thiol, the organic layer was washed the structures of whichwere proven by nuclear magnetic with Water and dried with anhydroussodium sulfate resonance spectra.

EXAMPLE 6 Distillation gave 210 g. of Employing the procedure of Example3 the product of HS Example 5 was reacted with ammonia in methanol to $1give a mixture of the cis and trans isomers of the formula B.P. 110 C.at 0.2 mm., n =1.5200, 61 1.080.

\suoHa) (0 CH) EXAMPLE 11 o 27.8 g. of the product of Example 10, 10 g.of 52% having the following properties: B.P. at 31 C. at .1 mm., HF inH20 and 50 of ethanol were refluxed for 18 1-4842i i425 RD obsenfedcalculated hours then cooled. The organic products were extracted .2834.The structures were further identified by nuclear with 100 of PentaneThe pentane layer was washed magnetlc resonance- 4 with water and driedover anhydrous sulfate. Distillation EXAMPLE 7 gave 27 of 16.2 g. of theproduct of Example 6 was mixed with E5 127 g. of HO(MeSiO) H and 1.4 g.of an acid clay Si-F sold under the name FILTROL l3 LM and stirred at 80to 85 C. for 6 hours. The methanol was then re- B P 162 c t 76.0 =1 4700nd d =1 ()50, moved at room temperature at .1 mm. for 2 hours to give119.2 g. of the copolymer EXAMPLE 12 HS SH When the following thiolatesare added to the follow- Si-(Me)O(Me SiO) i(Me)Si ing silacyclopentanesunder the influence of ultraviolet light of 2537 angstrom wave length.The following prodhaving a mercaptan equivalent of 1366 (theory equals tare btain d, 1397) and having the following properties: 11 1.4134 and aviscosity at 25 C. of 50 cps. 51 and Si EXAMPLE 8 To 46.5 g. of1-methyl-l-chloro-1-silacyclopentene-3 in in this and the followingexamples.

Thiolate Silaeyclopentane Product CnH COSH Z(0C2H5)2 CBHSCOSZI(OOZHS)2 CH CuH4COSH Z(CaH5)F CuH5H4COSZ(CiH5)F CH3C5H4COSH Z(C1sHa7) (0CH3)CH3CoHiCOSZ(CisH37) (OCHa) Z(0OCCH3)2 GOSH ooszmoooonm (OH3)2CeH3COSH(Z0) [(01 13)zCslEhCOBZO]n a doubled walled quartz reactor was added 100g. of EXAMPLE 13 liquid H S. The solution was stirred at C. andirradiated with a one watt ultraviolet lamp (2537 A.) for 8 hours. Themixture was warmed to room tempera- When the following thiolates areadded to the following silacyclopentenes in accordance with theprocedure of ture. After the excess H 5 had escaped there remainedExample 1, the following products are obtained.

Thiolate Silacyclopentene Product CIIHBECOSH ZlON=C(C2H5)(CHs)lz Ci7Ha5lON= 2 Ha)l2 cflnuoosrr Z{ON(CH3)2}2 CaH11COSZ[ON=C(CHa)2]2CQH5CHZCHZCOSHH Z(C@H4O1)O.5 CflHsCHZCHzCOSZ'(C6H4C1)O.5

CH COSH 62H, CH3COS\ (32H;

Si(CHZCH CFs)(OCHa) I si omomcra (ocna 'EXAMPLE 14 R' is independentlyhydrogen or an alkyl radical of from 1 to 6 carbon atoms, When thefollowing silacyclopentenes are added to a R is a monovalent hydrocarbonradical or a monovalent ten-fold excess of liquid H 8 and irradiatedwith ultra halohydrocarbon radical containing from 1 to carbon violetlight the following products are obtained. atoms,

Silacyclopentene Product 2(0113) (OOCCnHas) Hsz'wm) (00001111z(o,H5)(00H3) HSZ(CaH5)(OCH 2(05114 s 00H HSZ(CaH4CaH )OH Z(C1sH37)(0011 01120011 HSZ(C1sHa1)(OCHzCHzOCH Z((CH2)3CllBr Hszuorrmmmrzwmcmcnmocznnfln HSZ(CH2CH2CF3) (002115) ZZ(8uH4Cl){ON(CHa)2} l(E I ZeH4C1){0N( Ha)2} izwriiioii's'ilIIIIIIIIII .IIZIII [HSZ(CH )O} SlEXAMPIJE 15 X is halogen, hydroxyl or alkoxy, ketoxime, carboxyacyl oramineoxy, containing from 1 to 18 carbon atoms, R and X being free ofaliphatic unsaturation, 35 n is 0 or 1, and

m is 0 to 2, the sum of n m being not greater than two.

When CH COSZ(OCH is cohydrolyzed and cocondensed with the followingsilanes in the presence of FILTROL 13 LM the following products areobtained.

- P d t 1 t sflaues molpement zl lsz g 2. A copolymeric slloxanecont-ainlng at least one unit 10 CH COSZ(OCH l0 20%(C1Efa)zSi(OCH )z2 207i orimsio. of the formula 20 CH 0o 40 SiRuXmO I 2n1n naooszmocmn 11--45% CFgCHzCHzSKOH 10% 0119 5101 10% (0H3)3Si0.5. 45 111 which n and mare each 0 or 1, EXAMPLE 16 I Y is hydrogen or YC=O in which When (1)I-ISZ (CH )Ql or (2) HS Z Cl are cohydro- Y is hydrocarbon orhalohydrocarbon radicals free of lyzed and cocondensed with thefollowing sllanes the folaliphatic unsaturation, Y containing from 1 to30 carlowing products are obtained. bon atoms,

Silane mol percent Product mol product a- 20% ClC H SiOL5. 20%(CF3CHzCH2) (CH3)SiC12 20% CFaCHzCHzSi(CH )O. 20% C5H5CH(CH3)CH2S1(CH3)C12 20% CgHgCHKJHa) CHzSKCHs) 2- 10% C1sH37SiCla 10% CisH 7SiO1',5. 10%(CH3)3SiC1 10% (CH SiO.5.

That which is claimed is:

An organosllicorll compound of the formula R is independently hydrogenor an alkyl radical of 1 to Y 5 6 carbon atoms,

z Hn R is a monovalent hydrocarbon radical or a monovalenthalohydrocarbon radical of from 1 to 30 carbon atoms,

X is halogen, hydroxyl or alkoxy, ketoxime, carboxyacyl Y 18 hydrogen orO m which R caminlfoxy Ff 1 to 18 carbon atoms, I

Y is a monovalent hydrocarbon or halohydrocarbon radian X emg Tee ofahphatlc unsaturatlon the remam cal free of aliphatic unsaturation, Y'containing from ing Siloxane units in Said copolymer being essentially lto 30 carbon atoms, all of the formula in which 9 10 Ruusio 9. Thecomposition of claim 8 in which R is methyl,

.:2 m is 0 and R" is methyl.

2 10. The composition of claim 9 in which a is 2.

in which R" is a monovalent hydrocarbon radical or a monovalentReferences Cited halohydrocarbon radical of from 1 to 30 carbon atoms 5UNITED A S A NTS X l? and a h a f O 2,544,296 3/1951 Burkhard 260-448.2N

3. A compositlon of claim 1 1n whlch Y and each 2 802 853 8/1957 George260 448.2 N R ffifi f 1 3 h R th 1 2,863,898 12/1958 Merker 260--448.2 Nand.miseocomposition o 0 mm 1n w 1c is me y 1 3,445,496 5/1969 Ryan R 5.The COmpOSitiOIl of claim 3 in which R is methyl AS LEVOW i Examiner andX is chlorine.

6. The composition of claim 3 in which n is 0, X is SHAVER AsslstantExammer methoxy and m is 2.

7. The composition of claim 1 in which Y is YCO. 16

8. The composition of claim 2 where Y and each 204l58 R, 159.13;252-49.6; 260-465 E, 46.5 P, R is hydrogen. 46.5 Y, 399, 402.5, 448.2 B,448.2 D, 448.2 B, 448.8 R

